What Is the Average Height and Weight for a School-Age Child?

Approximately 18.5 percent of children between ages 2 to 19 qualify as having obesity, according to the Centers for Disease Control and Prevention. Obesity puts your child at increased risk for health problems later in life such as type 2 diabetes and heart disease.

Considering kids grow at different rates, it can be hard for parents to tell just by looking at their school-age child whether he or she is at a normal height and weight. Consider this quick guide of normal height and weight for children of all ages.

​Read more:​ What Is the Average Adult Male Height and Weight?

The range of "normal" for height and weight is quite broad in school-age children. These measurements are organized as percentiles on the CDC's age and weight charts. You can locate your child's height, weight and BMI and the percentile under which they fall.

At the age of 5, a typical child is about 43 inches tall and weighs about 43 pounds, according to the CDC. However, children at this age can vary by as much as 5 inches in height. A standard height is around 39 to 48 inches for a 5-year-old boy or girl, and a normal weight is between 34 and 50 pounds.

Children grow about 2 inches per year, with perhaps a bit more growth occurring between the ages of 6 and 8. At this age, a weight gain of about 6.5 pounds each year is standard. By 6 years of age, the normal height range for a child is about 42 to 51 inches. A healthy weight for a 6-year-old ranges between 36 to 60 pounds.

Even if your child falls within the normal ranges for both weight and height, she may be too heavy or too light for her height. While body mass index (BMI) measurements don't take body composition into account, they can be used as a guide to determine some factors of your child's health.

Any percentage between the 5th and 85th percentile on the body mass index-for-age charts is considered healthy, according to the CDC. Measurements above the 85th percentile are generally considered overweight, while measurements below the 5th are underweight. The normal BMI range for a 5- or 6-year-old boy or girl is from 14 to 17.

At 7-years-old, both boys and girls range from 45 to 54 inches, according to the CDC. By the time they reach the age of 9, the average height reaches between 48 and 59 inches.

Like younger children, girls in this age group generally have a wider weight span than boys. At 7, a boy typically weighs between 40 to 72 pounds, whereas girls usually weigh between 39 to 74 pounds. By 9, typical weights for boys are between 49 and 95 pounds, whereas girls usually weigh between 48 to 98 pounds.

A 7-year-old girl may have a slightly lower BMI than a boy of the same age. The standard BMI measurements for this age range between 13 to 18 for girls and 14 to 18 for boys. The standard BMI at 9 years old is the same.

While boys and girls are approximately the same height at age 10 (between 50 and 61 inches tall), they vary slightly by age 12, with boys typically ranging between 54 and 67 inches and girls ranging between 55 and 66 inches, according to the CDC.

As many children begin to enter puberty at this age, girls tend to be a bit heavier than boys. While a 10-year-old boy usually weighs between 53 to 109 pounds, girls of the same age often weigh between 53 to 113 pounds.

The recommended range for BMI considers these weight differences. A 10-year-old boy often has a BMI between 14 and 20, whereas a girl of the same age is expected to measure from 14 to 21. These recommended spans increase slightly for 12-year-olds, with boys ranging from 15 to 22 and girls ranging from 15 to 23.

​Read more:​ The Average Height and Weight by Age

As puberty begins, some kids develop more quickly than others. Two boys or girls of the same age may begin puberty at different points, yet still fall within "normal" growth, according to the American Academy of Pediatrics.

During puberty, your child's muscles and bones will grow, as will their body fat. Typically, girls develop a higher percentage of body fat, while boys tend to gain more muscle. Regular exercise is necessary for proper growth and development, according to the American Academy of Pediatrics. Fill your child's lunch box with plenty of nutrient-rich foods and encourage regular exercise.

Considering preteens experience puberty at different rates, height, weight and BMI all can vary quite a bit from child to child during these years. If you think your child may be at unhealthy levels, consult his or her pediatrician.